(1) Field of the Invention
The present invention relates to a pipe bender comprising a fixed die assembly and a clamp die assembly for holding a pipe therebetween, the clamp die assembly being swingable about the fixed die assembly within a selectd angular range in timed relation with a pipe feed rate to bend the pipe.
(2) Description of the Prior Art
This type of pipe bender has been proposed and put to extensive practical use in various forms. The known pipe bender comprises only one pipe bending section for one pipe feed mechanism. The pipe bending section includes a clamp die assembly horizontally swingable either clockwise or counterclockwise about a fixed die assembly to bend a pipe held therebetween. After bending the pipe, the clamp die assembly is swung in an opposite direction to return to an original position.
The above known construction has encountered difficulties in bending pipes to certain desired shapes. For example, a bent portion of the pipe contacts the pipe bender, in particular the bending section or a portion of the bender adjacent thereto, thereby obstructing further bending work to be carried out on the pipe. This is due to sizes of radii of curvature at bent positions of the pipe, directions of bend, a distance between two or more bent positions, and so on. Such a situation may make the further bending work impossible.